Quick Links

Cut the blade slot Make way with a dado blade. A standard 10-in. blade won’t let the insert sit flat, so use a single blade from an 8-in. dado set (above) to make a clearance slot for a standard 10-in. blade. Clamp a strip of scrapwood to the fence and position it right over the blade (right). The dado-blade kerf should go a little more than halfway through the insert (below). 1⁄2-in. plywood will be just below the top, and will need to be raised flush. For that job, I use 1⁄4-20 Allen leveling screws. I drill and tap through-holes for those screws so that I can adjust the height quickly while the insert is in place. Knowing where to drill is easy. Just use the holes you drilled to attach the stock insert to the plywood blank. Set up a 3⁄16-in. bit in the drill press and drill through-holes in those spots. Tap them using a standard 1⁄4-20 machinist’s tap. You may be surprised that you can thread Baltic-birch plywood, but it works great. Thread a 1⁄4-20 by 3⁄8-in.long Allen-head set screw into each hole. Remove the blade, install the new insert, and level it. Finishing cut. With the 10-in. blade installed and the scrap block clamped over the blade, raise the blade to its full height to create a perfect zeroclearance slot. 60 FINE woodworkIN g Cut the zero-clearance slot When the insert is level, it’s time to cut the blade slot. Do this by raising the spinning blade through the insert. Because a 10-in. blade doesn’t fit under the insert, I use a single 8-in. dado blade first to create a clearance groove to get the slot started, then change to the 10-in. blade to finish. Firmly clamp a piece of scrapwood to the fence and then position the fence so that the scrap is directly over where the blade will come through. This holds the insert down as you raise the blade to full height. It also backs up the cut and minimizes tearout. Cut the slot for the riving knife or splitter— For the standard blade insert, you’ll need to cut Drawings: Michael Pekovich